Physical fitness and various forms of exercise has increased considerably in the past number of years as well as the use of various devices permitting exercise in a confined area such as in a gymnasium or in a basement or separate room of a dwelling. Various forms of outdoor exercise also have increased in popularity and in particular cross-country skiing. Cross-country skiing has been determined to be one of the most effective forms of exercises, both as a cardiovascular fitness exercise and for simultaneously exercising nearly every major muscle group in the body without subjecting the body to the constant jarring and the possibility of injury which sometimes results from such types of exercise. However, due to the limited time periods during which cross-country skiing can be carried out, that is when there is adequate snow, individual's wish to be in shape for skiing as soon as there is adequate snow. Also, other individual's wish to derive the physical benefits from an exercise which closely simulates the cross-country skiing without actually performing the skiing in the outdoor environment.
Various devices have been developed for indoor exercise which provide both the cardiovascular and muscular development as provided by cross-country skiing, and which simulate cross-country skiing for those who wish to develop the muscle control and stamina for performing the same during the off season or for obtaining the physical benefits. Examples of such devices are shown in U.S. Pat. Nos. 3,941,377; and 4,023,795.
Other types of indoor exercise devices have been developed which simulate down-hill type skiing such as shown in U.S. Pat. Nos. 2,274,081; 3,475,021; 3,455,550; 3,408,067; and 3,711,089. Still other types of exercise devices such as shown in U.S. Pat. Nos. 1,766,089; 3,332,683; 3,554,541; and 3,711,090 provide a treadmill effect which is good for the leg muscles and cardiovascular fitness but not the arms.
Although exercise devices of the type shown in the above two mentioned patents pertaining the cross-country skiing perform satisfactory, they require a structure which is relatively expensive, especially when the exerciser is being developed for the home market in contrast to a more expensive exerciser for use by commercial establishments such as gynasiums, health spas, etc.
Therefore the need has existed for an improved exercise device and in particular a device which simulates cross-country skiing which can be produced economically yet which provides a sturdy, durable and smooth operating device which achieves the desired results as those achieved by cross-country skiing, and which is usable within a protected environment.